Shade some empty cells black to create a single group of black cells that are all connected to each other through their edges. No 2×2 cell area within the grid contains all black cells. Numbers to the left/top of the grid represent the groups of consecutive black cells which are in that row/column in order, either from left to right or from top to bottom. For example, a clue of “3 1” means that the row or column has a group of three consecutive black cells followed by a single black cell, separated by at least one white cell. A question mark (?) represents a group of consecutive black cells whose size is unknown; an asterisk (*) represents any number of unknown groups of black cells, including none at all.

Also, the shaded region must be able to be split into tetrominoes to form a valid LITS solution (meaning all tetrominoes are connected but no two tetrominoes sharing an edge are the same shape, including rotations and reflections).

For automatic solution checking, the shaded cells must be marked in black or a shade of gray. Note that if you are marking off the clues outside the grid, you should use any color but black or a shade of gray.

Cross the Streams (LITS) ("Threes") Serkan Yürekli

Undo CTRL + z Redo CTRL + y Erase selected mode Erase elements that belongs to the selected mode Delete all Erase problem or solution grid

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